I've been thinking about this for hours and I have to go with Breath of the Wild. Both games are absolutely amazing, but the reinvention of the formula while exploring the ideas and philosophies that created the original Zelda are what tips my vote for BoTW. Also the sound design is phenomenal. I can completely understand people going with Bloodborne though, and I adore the game, but I always thought it didn't quite execute on some of its ideas and themes as well as it could, and did noticeably have a few lacking areas (Byrgenwerth). It didn't feel quite fully realized.